Manipulation of light with subwavelength structures: plasmonics and metasurfaces

讲座内容：Manipulation of light with subwavelength structures becomes promising to realize efficient, highly integrated and miniaturized photoelectric devices. Plasmonic effect and metasurface could be two excellent candidates to meet the aforementioned requirements. Plasmonic effect is able to confine electromagnetic field at subwavelength space with metallic nanostructures, which has been widely applied to enhance various light-matter interactions even at nanoscale, such as photoluminescence, lasing and nonlinear optical signals. Besides, due to its environment-sensitive resonance properties, plasmonic effect has also be designed for trace level sensing of bio/chemical molecules. On the other hand, metasurfaces, consisting of unit cells with dual-subwavelength length scale, i.e. subwavelength lateral width and thickness, can manipulate propagation behaviors and properties (i.e. amplitude, phase, polarization, linear/angular momentum) of light in an arbitrary way. The control performance is comparable or even outperform traditional optical elements plus the expected miniaturized size. In this talk, I will briefly introduce the fundamentals and several typical applications of both plasmonics and metasurfaces.